The present invention relates generally to water purification systems and, in particular, to a point of use water purification apparatus utilizing a three-step purification process together with a piping bypass.
Water purification systems and methods are well known. Ensuring a safe and healthy water supply free from particle, chemical and microbiological impurities, such as bacteria and the like, is an ongoing concern in many parts of the world. The prior art has recognized this and provided various biocides and other systems aimed at exterminating and/or removing bacteria. Perhaps the most common means for exterminating and/or removing bacteria from water supplies is with the use of chlorine.
Chlorine is a powerful oxidizing agent and biocide and has been used for many years by municipal water treatment systems to disinfect water for personal and commercial use. Although it is an effective biocide and is economical to use, chlorine has been suspected to adversely affect living organisms when supplied at excessive levels beyond that required to exterminate the bacteria. In addition to initially treating the water, the water treatment system also typically supplies a residual, called the free chlorine residual, to maintain a level of chlorine sufficient to protect the water from bacteria throughout the water distribution system and the network leading to its point of use. In order to ensure an effective level of chlorine at the point of use farthest from the source, the chlorine level at points of use closer to the source will be higher than desirable. The impact of the free residual chlorine is disadvantageous and significant. The free chlorine residual alters the odor and taste of water as well as bleaches any colored organic objects including skin and hair. In addition, chlorine is itself suspected to be a carcinogen as well as a key component in the formation of trihalomethanes, which are also carcinogenic.
Despite the disadvantages and risks noted above, chlorine remains arguably the most economical and effective biocide for drinking water ever used and, therefore, its use as a biocide remains prevalent today. Many prior art systems exist that teach means to remove chlorine from water. Other prior art systems exist that teach other biocides as substitutes for chlorine. Most of these prior art removal systems or chlorine substitutes are either cost-prohibitive, difficult to apply, difficult to maintain, or a combination of all of the above.
It is desirable to provide an apparatus for removing chlorine from a municipal water supply that is both economical and simple to apply.
It is also desirable to provide an apparatus for removing chlorine that is simple to operate and maintain. It is also desirable to provide an apparatus that may be maintained while still sustaining water flow for the point of use.
It is, therefore, an object of the present invention to provide an apparatus to eliminate taste, odor, and health-related effects associated with the free chlorine residual provided from a municipal water supply. It is another object of the invention to provide an apparatus for removing chlorine from a municipal water supply at a point of use which apparatus is economical and simple to apply, operate, and maintain.
The present invention concerns a water purification apparatus for connection to a municipal water supply having a quantity of free residual chlorine. The present invention advantageously removes the free residual chlorine from the municipal water supply just before a point of use. The present invention accomplishes this by connecting the water supply into an inlet of a carbon filter. The carbon filter is preferably sized, based on the capacity of the water supply and the point of use, to absorb the free residual chlorine.
An outlet of the carbon filter is connected to an inlet of a particle filter. It is known in the art that carbon filters typically shed some carbon particles during normal use. The present invention recognizes this, and provides the particle filter, which is preferably a particulate filter that can remove these carbon particles as well as any other solid particles found in the municipal water supply. The particle filter is preferably sized to remove an amount of solids based on the properties of the water supply and the requirements of the point of use. For example, manufacturing requirements may be much stricter in terms of total dissolved solids (TDS) than that of a typical municipal water supply.
An outlet of the particle filter is connected to an inlet of an ultraviolet light source for sanitizing, or disinfecting, the water prior to its point of use. It is known in the art that carbon filters can create an environment suitable for microbiological growth because such filters contain a dark and humid environment. The present invention recognizes this, and provides the ultraviolet light source, which advantageously disinfects the water without impacting the taste or the odor of the water. The ultraviolet light source also disinfects the water instantaneously with no residual effects. The outlet of the ultraviolet light source is connected to the point of use of the water, such as a residence or office building.
The apparatus includes a bypass conduit connected in parallel with the purification units (the carbon filter, the particle filter, and the ultraviolet light source). The bypass is connected between the water supply and the point of use. The water purification apparatus further includes associated valves that are provided to isolate the purification units for performing maintenance on the apparatus.
The present invention advantageously contemplates utilizing low-cost, commercially available standard equipment to eliminate chlorine from drinking water and from water used in food, beverage, and related uses. Furthermore, the present invention advantageously provides the bypass conduit to allow easy maintenance of the components of the present invention. The present invention also extends the life or operating hours of the carbon filter, the particle filter and the ultraviolet light source by utilizing the bypass conduit during periods when the purification process is not needed. For example, during closing hours of a business establishment, office, etc. The bypassed chlorinated water can flow until it is necessary to go back to the purified water during demand or peak use periods. This operation also keeps the bypass conduit bacteria free with the chlorinated water flow. The present invention, therefore, is a low-cost yet effective and efficient means for removing chlorine from a municipal water supply. In addition to domestic potable water use, the present invention contemplates uses in many industrial sectors where chlorine can affect the process or final product characteristics including, but not limited to, the paper, textiles, food, and beverage industries.
In addition, the present invention is scalable in that it is not limited to certain values of water flow, the amount of free residual chlorine, or the amount of TDS. Filter and piping sizes are dependent on a number of factors, including water flow and the amount of free chlorine measured in the water. The components of the present invention (the carbon filter, the particle filter, and the ultraviolet light source) can be custom designed for each specific point of use water distribution system, and it also is within the scope of the present invention to mass produce the components for typical residential applications.